Heat exchanger

ABSTRACT

Provided are exemplary embodiments, which may include a heating system with one or more heat exchangers. The heat exchangers may be capable of transferring heat in, to, and/or from the heating system to reduce inefficiencies, and/or allow the heating system to operate in a relatively more efficient manner.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to and benefit of U.S. ProvisionalApplication No. 60/894,409, entitled “Heat Exchanger” and filed on Mar.12, 2007.

TECHNICAL FIELD

The present disclosure relates, generally, to heating systems and, inparticular, to a heat transfer of a heating system.

BACKGROUND

Various heating systems, including fireplaces and furnaces for homeinstallations, may have been made available to consumers in recent yearswith improved control systems. Despite improvements, such heatingsystems may be limited in the ability to control the heat distributionfrom the heating system to the area to be heated.

For example, while current heating systems have frequently utilizedvarious techniques to separate the combustion air from the room air,such as direct air venting systems, very little has been done to improveheat transfer and distribution, and/or increase the efficiency of thesystem. This efficiency may include the amount of heat transferred tothe surrounding area.

SUMMARY

In accordance with various aspects of exemplary embodiments, a heatingsystem may include heat exchangers, such that the heating system mayoperate more efficiently. In accordance with an exemplary embodiment, anexemplary heating system may include a combustion air path, a convectionair path, as well as other pathways for air and/or heat exchangingconfigurations. The heating system may include various types of heatingconfigurations, such as fireplaces, stoves, furnaces or other likeheating systems. An air intake is configured to receive external airinto the heating system, while an exhaust vent is configured to removeexhaust from within the heating system. Both the air intake and exhaustvent can be configured in various manners, shapes and sizes forproviding the respected air intake and exhaust removal functions, aswell as heat exchange.

In accordance with one aspect of exemplary embodiments, the heatingsystem may be configured to include heat exchangers to increase theefficiency of the system.

BRIEF DESCRIPTION OF THE DRAWINGS

The exemplary embodiments may be described in conjunction with theappended drawing figures in which like numerals denote like elementsand:

FIG. 1 is a diagram of an exemplary heating system according to anexemplary embodiment;

FIG. 2 is a perspective view of an exemplary heat exchanger according toan exemplary embodiment;

FIG. 3 is a user interface according to an exemplary embodiment.

DETAILED DESCRIPTION

The present disclosure may describe various functional components. Itshould be appreciated that such functional components may be realized byany number of hardware components, electrical and mechanical, configuredto perform the specified functions. In addition, exemplary embodimentsmay be practiced in any number of heating system contexts, and thefireplace systems described herein are merely one exemplary application.

Referring now to FIG. 1, in accordance with an exemplary embodiment, asolid fuel heating device 10 having a combustion chamber 12 isillustrated. In an embodiment, a heat exchange arrangement in the formof hollow pipes 19 can be disposed towards the top end of combustionchamber 12 and may be heated hot air from combustion chamber 12. Ambientair, as indicated by arrows 22, may be circulated through hollow pipes19 by a fan 21 mounted in a side wall of the heating device, or anyother convenient location, such as proximate the hot air exhaust area,to exhaust heated air 20 from pipes 19 into the ambient air, in adirection indicated by arrows 22. This may be accomplished to heat thesurrounding area of heating device 10. Fan 21 may be configured invarious locations for circulating ambient air through pipes 19, withsuch pipes 19 being arranged in various manners for discharging heat tothe surrounding area.

In an embodiment, the convection, combustion and/or air inlet air flowpathways and/or systems may also be used in other manners by utilizingheat transfer devices to extract heat, including flat and/or accordionplate heat exchangers, air flow passages for exhaust and/or convectionair, casting, hot air intake, and/or other methods and systems fordischarging heat to the surrounding area. The utilization of heatexchangers with a stove may increase the efficiency of the system,increase the convection temperature, and/or lower the exhausttemperature, and/or combinations thereof. Heat exchangers may beutilized in many portions of the heating system to generally reduceinefficiencies.

Furthermore, combustion and convection air flow may be configured to beparallel, counter, and/or cross flow, and/or combinations thereof tofurther increase efficiency. In an embodiment, heat exchange between theconvection and combustion air, heat exchange between the air intake andthe exhaust air, mixing the exhaust air with the air intake, etc. maymake the system more efficient.

Heating system 10, as herein illustrated in the exemplary embodiment,may be a biomass pellet, fuel, and/or grain-fed, and/or other fuel,and/or combinations thereof, space-heating stove. The system may includea “key,” which may allow the system to utilize different fuels. The keymay be added to allow the use of various type of fuel. The system mayallow a user to switch fuel type without shutting down the system.

In an embodiment, system 10 may include a hopper 23. Hopper 23 may beconfigured for storage of fuel sources, such as solid fuel pellets 24,for example. Hopper 23 may be various sizes, shapes, and configurationsfor storage of fuel. In an exemplary embodiment, fuel pellets 24 may befed into a fuel bed 25 of combustion chamber 12 by an auger 26 feeding achute 27.

In the exemplary embodiment, solid fuel pellets 24 entering combustionchamber 12 may be projected into fuel bed 25 by gravity and supported bya support mechanism in the form of a support tray 28. Support tray 28may be fixedly secured under the bottom, open end of the inner wall 16.An ash collecting tray 29 may be removably secured under this supporttray 28 and accessible through a door 30. A sensor may be included,which may alert a user that the ash pan is full. This may indicate thatthe pan should be emptied. If the pan is not emptied, the system mayshut down, or other sequence, to protect the system.

Solid fuel pellets and grains (fuel) 24 may also be fed from the bottomor the side of the unit, or any other configuration for providing fuel,and the like, onto fuel bed 25. For example, rather than hopper 23and/or auger 26, many other mechanisms or systems for conveyingmaterials may be suitably implemented.

The system may be capable of operating a high-efficiency burn mode, or aclean burn mode, which may be user selectable.

Shown in FIG. 2 is a perspective view of an exemplary heat exchangingdevice 100. In an embodiment, device 100 may be utilized through theheating system to increase efficiency. Device 100 may include agenerally cylindrical portion 102 and a generally irregular surfacedportion 104. Multiple devices 100 will be located in areas 19 and 20 ofFIG. 1.

As seen in FIG. 2, the irregular surfaced portion 104 is typicallyconfigured with more surface area than the cylindrical portion 102.However, the configuration of the irregular surfaced portion 104 shownin FIG. 2 is not meant to be limiting. While the irregular surfacedportion 104 portion is show having multiple fins, it should beunderstood that other suitable configurations may also be utilized aswill be further discussed below.

In operation, cool convection air passes thru an internal part of thisdevice 100. The convection air is then heated by the exhaust passingthru the irregular surfaced portion 104. The design of the irregularsurfaced portion 104 provides more heat transfer than standard somewhatsmooth and/or regular surfaced heat exchangers. As such, the design ofthe irregular surfaced portion 104 allows more heat to be transferredgenerally from the interior of the device 100 to the exterior of thedevice 100.

It should be understood that the device 100 can be made by extrusionmethod using aluminum. The device 100 may also be cast into variousshapes using different materials based on the geometry that meets thedesign needs. As such it should further be understood that multipleconfigurations of the irregular surfaced portion 104 may be used basedon design configurations. Some examples include but are not limited toaccordion-type, flat-type, corrugated-type, heat pipe-type, and spiralplated-type configurations.

Many different types and configurations of heat exchangers may beutilized with the system. A corrugated surface plate, or a casting madefrom copper or other high heat transfer coefficient material may bepositioned between different air flows to enhance heat transfer.Utilizing finned tubes may further increase the surface area andincrease the heat transfer characteristics of the system. Furthermore,the alteration of the air flow devices to create turbulence or otherdisruption may further increase efficiency.

Other types of heat exchangers, such as heat pipes, or condensers mayalso be utilized to enhance heat transfer, as they may utilize the phaseshifts of fluids to release heat at a much higher rate. Furthermore,there may be other heat exchangers that enhance heat transfer such ascoaxial venting, radiator, spiral plated exchangers, and/or any otherheat exchanger that may enhance heat transfer.

Referring now to FIGS. 1 and 3 in accordance with exemplary embodiments,user interface 61 includes a keypad-type configuration, with a display76. In embodiments, display 76 may be an LED-type display, and/or anLCD-type display. Other display types may be utilized without strayingfrom the concepts disclosed herein.

Furthermore, user interface 61 may be configured to allow a user tocontrol and/or manipulate the operation of the solid fuel biomass pelletheating device 10, such as the system illustrated in FIG. 1.

Controller 60 may be configured to control the motor(s) and the fans,and inputs and operating parameters utilizing information from sensorslocated throughout the system. To start the operation of a biomasspellet device 10, a user may actuate the button labeled “Start” 78. Thismay cause the pellets to be automatically fed to the burner and ignitedby an ignition device, to create an initial fuel bed. Other steps maythen be accomplished to start the operation of heating system 10, suchas starting the system with a fire starter, and/or starting with onefuel and continuing the burn with another fuel. Other ignition methodsmay be utilized, including utilization of an air pump and/or an igniterto assist in creating a torch effect, and/or more than one ignitionsource. Furthermore, a user may turn off the heating deice by depressingthe button labeled “Stop” 80.

In an embodiment, the “Service” actuator 82 may activate diagnostics forthe system. The diagnostics may include tuning the bum to compensate foratmospheric conditions, and/or variations in fuel, and fuel quality. Itwill be appreciated that the diagnostics of the system may include manyother diagnostics.

In an embodiment, the user may select a desired mode of operation ofdevice 10 by inputting desired parameters into the controller by the useof interface pad 61. Interface pad 61 can also be provided with heatlevel buttons 73, which may control the amount of heat produced by thesystem. This may increase or decrease the temperature in combustionchamber 12. This increase may cause an increase in the temperature ofthe heated air released by the biomass pellet device through the heatexchanger located above the flame, which may be regulated by a separatefan. All of these operating parameters may be capable of being steppedup or down, to maintain relatively optimum performance levels and/or todecrease inefficiencies of the system, according to the desired heatperformance required of the device.

Additionally, the entire system can operate from a remote thermostat toregulate all of these operating parameters based at least in part uponthe setting(s) of the thermostat. User interface 61 may also be removedfrom the system and be used remotely. A “Prime Stove” actuator 72 may beprovided, which may be capable of activating a method for manuallypriming the heating device. This may be due to the various types and/orqualities of the fuel being utilized. Priming may not be necessary forall fuels, types, and/or qualities.

Inputs from actuators may be sent to the controller, which may regulatethe speed of the motor, which drives the ash auger. Control switches 73may also be utilized to set a desired BTU output of the pellet stove.Through the software of the controller, the type of fuel andsubstantially optimal operating conditions of the device may beregulated and maintained.

User interface 61 may also include a fuel selection button 70, which maybe configured to indicate to the controller the fuel that will be used.Different choices for fuel may appear within display 64. The user maythen depress “Heat” actuator 74, which may allow a user to adjust theheat level using buttons 73. This may allow the controller to controlvarious aspects of the system based at least in part upon the type offuel being used by the system. In an embodiment, the types of fuel shownare solid fuels. However, other fuels, such as non-solid fuels, may alsobe utilized.

User interface 61 may be attached to the system, or may be a remotecontrol. Furthermore, user interface 61 may also be capable ofcommunicating with other devices within the heating environment tofurther control the operation of the system. In one embodiment, anotherdevice may be a temperature sensor that may interface with the system.

The present invention sets forth a heat transfer controller that isapplicable to various heating system applications. It will be understoodthat the foregoing description is of exemplary embodiments of theinvention, and that the invention is not limited to the specific formsshown. Various modifications may be made in the design and arrangementof the elements set forth herein without departing from the spirit andscope of this disclosure. For example, the sensors utilized are notlimited to those shown herein. Furthermore, other user interfaces may beutilized as well. Many other processors/controllers, as well as sensorsmay be utilized without straying from the concepts disclosed herein.These and other changes or modifications are intended to be includedwithin the scope of the present invention, as set forth in the followingclaims.

1. A heating system, comprising: a combustion air pathway capable ofallowing air to pass to a combustion chamber; a convection air pathwaycapable of receiving heat from the system and heating the areasurrounding the heating system; an air intake pathway capable ofallowing air to enter the heating system, and one or more heatexchangers configured in the combustion, air intake, and/or theconvection air pathways, capable of exchanging heat to decreaseinefficiency of the heating system.
 2. The heating system according toclaim 1, wherein the one or more heat exchangers comprises at least oneof an accordion-type, flat-type, corrugated-type, heat pipe-type, spiralplated-type, and finned-type configuration.
 3. The heating systemaccording to claim 1, wherein the one or more heat exchangers comprisesat least on of a condenser, a radiator, a high heat coefficientmaterial, and a cast material.
 4. The heating system according to claim3, wherein the one or more heat exchangers comprises a generally liquidmaterial.
 5. The heating system according to claim 3, wherein the castmaterial comprises at least one of copper and aluminum.
 6. The heatingsystem according to claim 1, wherein the air pathways are configured inat least one of a parallel flow configuration, a cross flowconfiguration, and a counter flow configuration.
 7. The heating systemaccording to claim 1, wherein air flow from the air pathways is mixed.8. The heating system according to claim 1, wherein turbulence occurs inthe air flow in the air pathways.
 9. The heating system according toclaim 1, wherein a disruption occurs in the air flow in the airpathways.
 10. The heating system according to claim 1, furthercomprising a coaxial vent.
 11. A pellet stone heating system,comprising: a combustion air pathway capable of allowing air to pass toa combustion chamber; a convection air pathway capable of receiving heatfrom the system and heating the area surrounding the heating system; anair intake pathway capable of allowing air to enter the heating system,and one or more heat exchangers configured in the combustion, airintake, and/or the convection air pathways, capable of exchanging heatto generally decrease the inefficiency of the heating system, whereinthe one or more heat exchangers comprises at least one of anaccordion-type, flat-type, corrugated-type, heat pipe-type, spiralplated-type, and finned-type configuration.
 12. The heating systemaccording to claim 11, wherein the one or more heat exchangers comprisesat least one of a condenser, a radiator, a high heat coefficientmaterial, and a cast material.
 13. The heating system according to claim12, wherein the one or more heat exchangers comprises a liquid material.14. The heating system according to claim 12, wherein the cast materialcomprises at least one of copper and aluminum.
 15. The heating systemaccording to claim 11, wherein the air pathways are configured in atleast one of a parallel flow configuration, a cross flow configuration,and a counter flow configuration.
 16. The heating system according toclaim 11, wherein air flow from the air pathways is mixed.
 17. Theheating system according to claim 11, wherein turbulence occurs in theair flow in the air pathways.
 18. The heating system according to claim11, wherein a disruption occurs in the air flow in the air pathways.